Shigehisa Tamaki

Superior survival of blood and marrow stem cell recipients given maternal grafts over recipients given paternal grafts

During the reproductive period, mothers and offspring exchange hematopoietic cells and develop a form of immunological tolerance bidirectionally. To examine whether previous experience of such communication has any remote effect when maternal hematopoietic cells are later transplanted to the children, we retrospectively compared the outcomes of blood and marrow stem cell transplantation from maternal donors (nu2009=u200946) to those from paternal donors (nu2009=u200950) by using the database of the Japanese nationwide surveys for adult hematopoietic cell transplants between 1990 and 1998. At 5 years, recipients of maternal hematopoietic cells had a significantly higher overall survival than patients receiving paternal grafts (60% vs 32%, Pu2009=u20090.006). Although no significant difference was observed in the occurrence of severe acute GVHD (grade ⩾III) and the relapse of malignant diseases between two groups, the probability of non-relapse treatment-related mortality was significantly lower after maternal donor transplants. Furthermore, multivariate analysis revealed that parental donor type was the only factor significantly associated with overall survival. In conclusion, our analysis indicates superior survival of maternally donated recipients in hematopoietic stem-cell transplantations from biological parents. This finding has important implications in the selection of alternative familial donors, and warrants further prospective analysis of parental donor transplantations. Bone Marrow Transplantation (2001) 28, 375–380.

Tamibarotene As Maintenance Therapy for Acute Promyelocytic Leukemia: Results From a Randomized Controlled Trial

PURPOSEnThe introduction of all-trans-retinoic acid (ATRA) has significantly improved outcomes for acute promyelocytic leukemia (APL), although a subset of patients still suffer relapse. The purpose of this study was to evaluate the role of maintenance therapy with the synthetic retinoid tamibarotene in APL.nnnPATIENTS AND METHODSnPatients with newly diagnosed APL in molecular remission at the end of consolidation therapy were randomly assigned to receive ATRA or tamibarotene, both orally, for 14 days every 3 months for up to 2 years.nnnRESULTSnA total of 347 patients were enrolled. Of the 344 eligible patients, 319 (93%) achieved complete remission. After completing three courses of consolidation therapy, 269 patients underwent maintenance random assignment. The relapse-free survival (RFS) rate at 4 years was 84% for the ATRA arm and 91% for the tamibarotene arm (hazard ratio [HR], 0.54; 95% CI, 0.26 to 1.13). When the analysis was restricted to 52 high-risk patients with an initial WBC count ≥ 10.0 × 10(9)/L, the intergroup difference was statistically significant, with 4-year RFS rates of 58% for the ATRA arm and 87% for the tamibarotene arm (HR, 0.26; 95% CI, 0.07 to 0.95). For patients with non-high-risk disease, the HR was 0.82 (95% CI, 0.32 to 2.01). The test for interaction between treatment effects and these subgroups resulted in P = .075. Both treatments were generally well tolerated.nnnCONCLUSIONnIn this trial, no difference was detected between ATRA and tamibarotene for maintenance therapy. In an exploratory analysis, there was a suggestion of improved efficacy of tamibarotene in high-risk patients, but this requires further study.

BCR-ABL1 mutations in patients with imatinib-resistant Philadelphia chromosome-positive leukemia by use of the PCR-Invader assay

BCR-ABL1 kinase domain mutations were evaluated in 60 imatinib-resistant patients with Philadelphia-positive (Ph(+)) leukemia using PCR-Invader assay and direct sequencing. In chronic myelogenous leukemia (CML)--chronic phase (CP), 5 had P-loop mutations and 3 had T315I mutations. CML-CP patients with high Sokal score showed significantly higher incidence of mutations. P-loop mutations were associated with higher risk of disease progression. In CML-advanced phase, P-loop mutations and T315I mutation were associated with significantly shorter survival. In Ph(+) acute lymphoblastic leukemia, overall survival was poor irrespective of mutational status. The PCR-Invader assay is useful for screening of mutations and prediction of prognosis.

Phase I/II study of tandem high-dose chemotherapy with autologous peripheral blood stem cell transplantation for advanced multiple myeloma

The efficacy and safety of high-dose chemotherapy with tandem autologous peripheral blood stem cell transplantation (auto-PBSCT) were evaluated in a multicenter clinical study of patients with advanced multiple myeloma. Eligible patients (n = 40) were consecutively enrolled in the phase I/II study and received 2–4 cycles of vincristine–adriamycin–dexamethasone regimen. The responding patients underwent PBSC harvesting following high-dose cyclophosphamide and filgrastim administration. The first auto-PBSCT (n = 32) following high-dose melphalan (200 mg/m2) was performed within 2 months of PBSC harvesting; the second auto-PBSCT (n = 28) was scheduled 3–6 months later. Treatment-related mortality was 2.5% (n = 1) throughout the protocol. Grade 4 nonhematologic toxicity occurred in 12.5 and 14.3% of the first and second auto-PBSCT patients, respectively. All but one patient (who died) achieved hematopoietic recovery. For the 28 patients completing the second auto-PBSCT, the results were favorable with a response rate of 65% (complete response rate = 27.5%, n = 11); the five-year progression-free survival and overall survival were 20.3 and 66.5%, respectively. In conclusion, high-dose chemotherapy with tandem auto-PBSCT is feasible and safe with a favorable response rate in treating advanced multiple myeloma in Japan.

Tamibarotene maintenance improved relapse-free survival of acute promyelocytic leukemia: a final result of prospective, randomized, JALSG-APL204 study

Between April 2004 and December 2010, we conducted a prospective randomized controlled study comparing tamibarotene with all-trans retinoic acid (ATRA) in the maintenance therapy of newly diagnosed acute promyelocytic leukemia (APL), and here report the final results of this study with a median follow-up of 7.3 years. Of 344 eligible patients who had received ATRA and chemotherapy, 319 (93%) achieved complete remission (CR). After completion of three courses of consolidation chemotherapy, 269 patients in molecular remission underwent maintenance randomization, 135 to ATRA (45u2009mg/m2 daily), and 134 to tamibarotene (6u2009mg/m2 daily) for 14 days every 3 months for 2 years. The primary endpoint was relapse-free survival (RFS). The 7-year RFS was 84% in the ATRA arm and 93% in the tamibarotene arm (pu2009=u20090.027, HRu2009=u20090.44, 95% CI, 0.21 to 0.93). The difference was prominent in high-risk patients with initial leukocytesu2009≥u200910.0u2009×u2009109/L (62% vs. 89%; pu2009=u20090.034). Tamibarotene was significantly superior to ATRA by decreasing relapse in high-risk patients. Overall survival after randomization did not differ (96% vs. 97%; pu2009=u20090.520). Secondary hematopoietic disorders developed in nine patients, secondary malignancies in 11, and grade 3 or more late cardiac comorbidities in three. These late complications did not differ between the two arms.

A phase II study of lenalidomide consolidation and maintenance therapy after autologous PBSCT in patients with multiple myeloma

The efficacy and safety of lenalidomide (LEN) consolidation therapy and subsequent LEN maintenance therapy after high-dose therapy with autologous peripheral blood stem cell transplantation (auto-PBSCT) were evaluated in patients with newly diagnosed symptomatic multiple myeloma (MM). Forty-one patients were enrolled and received high-dose dexamethasone (DEX) therapy as an initial induction. The patients who did not respond to the DEX therapy were further treated with four cycles of bortezomib plus DEX (BD) induction therapy. For patients who responded to BD, PBSC harvesting was scheduled following high-dose cyclophosphamide and filgrastim administration. After PBSC harvesting, high-dose chemotherapy of melphalan with auto-PBSCT was performed. One hundred days after auto-PBSCT, patients received consolidation therapy consisting two cycles of LEN plus low-dose DEX (Ld) and LEN maintenance therapy. Only one death occurred during mobilization therapy, but the protocol developed in this study was considered generally safe to provide. Overall response rates after consolidation and maintenance therapies were 73.7% and 81.6%, respectively. Two-year progression-free survival and overall survival were 76.3% and 92.1%, respectively. These observations suggest that LEN consolidation and maintenance therapy are effective and safe, and provide favorable response rates in patients with MM.